Six principal investigators in Building 68 of the MIT Department of Biology, proposed to use high-performance digital microscopy to analyze protein distribution, axon guidance, cell motility, chromosome segregation and bacterial cell division in live and fixed cells. This work will be undertaken with an applied Precision DeltaVision Multi-Model Microscope (MMM) that combines laser-scanning and deconvolution- based wide field imaging into a particularly powerful instrument. The microscope will be integrated into a powerful server-based environment so that data can be effectively gathered and analyzed by various users. The Constatine Paton lab will use the MIT MMM in place of a confocal previously available at Yale to examine axon targeting in live visual cortexes fro rodents and amphibians. The goal of the work is to understand how neuronal activity affects axonal development. The Garrity lab will use the microscope to examine axon guidance in live Drosophila tissues that carry GFP markers in specific neurons. Analysis of targeting by these neurons in different genetic backgrounds will reveal the molecular basis of axon guidance in the fly eye. The Gertler lab uses liver-cell imaging to examine actin-based motility in cells derived from wild type and mutant mice. Its immediate goal is to determine how the Mena protein regulates the actin cytoskeleton. The Grossman lab will use the MMM facility is to examine the spatial relationship among proteins involved in chromosomal replication in B. subtilis. Three is a remarkable degree of localization of subtilis, replication proteins and high-resolution imaging of live cells is expected to reveal how this localization varies with the cell division cycle. The Sinskey laboratory will exploit spatially resolved and quantitative information t derived from deconvolved images to examine the biosynthesis of the critical PHA polymer in R. eutropha. PHA is of central importance to the metabolism of cells and has potential application in degradable plastics. The Sinskey lab's work is an early used of advance imaging in metabolic engineering. The Sorger Lab will use the high acquisition speed of the MMM to capture three-dimensional time lapse data on chromosome segregation in wild type and knockout mouse and yeast cells. The goal is to uncover mechanisms responsible for the high accuracy of chromosome segregation. Finally, the users group will, in conjunction with Applied Precision, present two advanced training courses per year at MIT. These will be critical for the long-term operation of the Multi-Model Microscope facility and should be of general benefit to microscopists in the Boston area.